I have only been there for lunch, but I really like Alma Cucina in the 191 building. Meehan's is good for bar food and lunch, and at least yesterday at lunch it wasn't overwhelmed by mart-goers. Hsu's for Chinese.

For lunch, you might want to check out Broad St. in the Fairlie-Poplar district. A bit further from the mart, but there are some great spots that are only open at lunch, like Rosa's Pizza (NY style), Dua for pho, and Reuben's NY style deli. Around the corner on Peachtree (across from Woodruff park) there's a good Korean place called Blossom Tree too. Hope that gives you some non-traditional lunch options.